Abstract: A fail-safe service machine for the power steering system of automotive vehicles includes a pair of pumps each driven by electrical power from a vehicle under service, and a suction/delivery probe extending into the power steering system reservoir of the vehicle, both to remove old power steering fluid, and to simultaneously deliver new power steering fluid.

Abstract: An automotive fluid service machine for changing fluids such as automatic transmission fluid, power steering fluid, and engine coolant, includes a cabinet with a unitary integral fluid reservoir defined by a lower portion of the machine cabinet. This lower cabinet portion which integrally defines the fluid reservoir also provides a machinery deck to which the components of the machines are mounted. A cap portion of the cabinet provides a cavity for protecting the components mounted to the machinery deck and also provides a control panel for the machine in addition to providing fluid fill and drainage basins improving the convenience and safety of use for the machine. The safety of a service area is improved by the machine because a very low center of gravity for the machine reduces the risk of tipping of a machine and of spilling fluids. Thus, environmental concerns from such spills as well as the risk of personnel slips and falls on spilled fluids are reduced.

Abstract: A fail-safe transmission service machine allows old ATF to be pumped out of a transmission while the vehicle engine runs, and responsively pumps a matching volume of new ATF into the transmission so that dry running of the transmission can not occur. If the supply of new ATF runs out or if power to the service machine is interrupted, the machine reverts to closed loop fluid circulation for the transmission. A hydraulic rectifier provides for universal connection of hoses between the transmission cooler fluid circulation loop of the vehicle and the service machine. An alternative embodiment of the machine allows for similarly fail-safe exchange of power steering fluid from a vehicle, and replacement of the old fluid with new power steering fluid.